For racing it lets you trim very easily and precisely while under heavy load. This is because we adjust trim very very often when racing, especially when riding upwind with lots of load from the fins. It really helps so that you can trim your kite to your body position, instead of the other way around.
The downside is that you end up with a lot of extra line dangling. For racing its okay but for freestyle or freeriding it'll get in the way, especially of unhooking. But moreso, you just don't need to adjust that often freeriding so there isn't much point.
My own bars are similar, but I also have a system to adjust the back lines while riding. I find it useful for changing kite sizes, but also to adjust or stealing line imbalances. I find if I'm looping a kite often to one side then my lines stretch unevenly, even over the course of one day.